Li_3V_(2-x)Ce_x(PO_4)_3/C的制备及电化学性能

Synthesis and electrochemical performance of Li_3V_(2- x)Ce_x( PO_4)_3/ C

采用溶胶-碳热法制备Li3V2-xCex（PO4）3／C=0、0．02、0．04和0．06）复合材料，通过XRD、SEM、恒流充放电和电化学阻抗谱等测试，研究Ce^3＋掺杂对材料的影响。Ce^3＋的适量掺杂没有改变结构，对形貌也没有明显的影响，但可降低一次颗粒的尺寸，提高电导率。掺杂量x=0．04的材料以2．0C在3．0-4．8V循环，首次放电比容量为148．3mAh／g，第50次循环的容量保持率为85．1％。

Li3V2-xCex（PO4）3/C （x = 0,0. 02,0. 04 and 0. 06 ） composites were prepared by sol-carbonthermal method. Effects of Ce^3＋ doping to the material were studied by XRD, SEM, galvanostatic charge-discharge and electrochemical impedance spectra tests. Suitable Ce^3＋ doping did not change the structure, had not obviously effect on morphology, however, the size of primary particles was reduced, the electronic conductivity was increased. When the material in which doping amount x = 0. 04 was cycled in 3.0 -4. 8 V with 2. 0 C,the initial specific discharge capacity was 148. 3 mAh/g,the capacity retention was 85.1% at the 50th cycle.